NEBOSH Diploma Unit B - Revision- Questions with
verified answers
Comment on its value as a measure to control contaminants (dilution ventilation)
Ans✓✓✓-This method is only suitable where there is a relatively low
concentration of high WEL contaminant which is given off slowly. It is not suitable
where operators are in close contact with the source of contamination
Define 'Workplace exposure limit'. Ans✓✓✓-defined as "maximum concentration
of an airborne substance, averaged over a reference period, to which employees
may be exposed by inhalation".
Define anxiety and depressions Ans✓✓✓-Anxiety - "feeling of unease, such as
worry or fear that can be mild or severe" (NHS)
Depression is when you have feelings of extreme sadness, despair or inadequacy
that last for a long time.
Define the term ' relative humidity' Ans✓✓✓-Relative humidity is an expression
of the ratio of water vapour in air relative to the maximum concentration of water
vapour that would be required to saturate air at the given temperature
Define the WBGT heat stress index Ans✓✓✓-WBGT is a heat stress index used to
make a prediction of the heat stress on a worker carrying out a particular rate of
work.
WBGT is calculated from:
WBGT = 0.7 WB + 0.3 GT indoors
,or
WBGT = 0.7 WB + 0.2 GT + 0.1 DB outdoors
where:-
- WB is the wet build temperature
- GT is the globe thermometer temperature
- DB is the dry bulb temperature
The index value (WBGT) must be used in conjunction with empirical
recommendations (set out in ISO 7243) to indicate a level that is safe for most
people who are physically fit and in good health.
Different values are quoted to distinguish persons acclimatised or unacclimatised
to heat.
If conditions of exposure fluctuate, a time-weighted average exposure can be
derived and used
Define what the Equality Act 2010 means by a disabled person Ans✓✓✓-a
person is disabled if they have "a physical or mental impairment which has a
substantial and long-term adverse effect on their ability to carry out normal dat-
to-day activities".
Describe a test that can be used to detect genetic mutation Ans✓✓✓-The most
well known test is the Ames test.
,This involves exposing the mutagen to a specific strain of bacteria that will not
normally grow in a histidine-deficient growth medium.
Mutagens will cause a mutation in the bacteria allowing them to grow in a
histidine-free medium
Describe an example of a retrospective cohort study Ans✓✓✓-Asbestos exposure
and lung disease
2 populations are identified which differ only by the fact that one group has been
historically exposed to asbestos and the other has not.
Evidence of exposure is collected from health records.
Medical surveillance is then carried out to gather data about the prevalence of
lung disease in these 2 groups.
This is reinforced with other health data.
Statistical analysis is then carried out to see if a link between lung disease and
historic asbestos exposure can be proven to exist.
Describe how oxygen enters the bloodstream Ans✓✓✓-Inhaled air passes
through the nose or mouth, down the trachea, bronchi and bronchioles, into
alveoli.
Here, the very thin lining of alveoli and blood vessels flows oxygen to diffuse into
the bloodstream where it then diffuses into red blood cells and is bound to
haemoglobin. Carbon dioxide is excreted by the same process
Describe how the ear converts sound waves into nerve stimulation to the auditory
centre of the brain. Ans✓✓✓-The ear transmits nerve impulses to the brain as a
, result of detecting and transmitting mechanical vibration through the outer ear,
the middle ear and the inner ear.
Describe measures that can be taken to reduce individual stress by improving
work relationships. Ans✓✓✓-Interpersonal skills training:-
Interpersonal skills involve the ability to communicate and build relationships
with others. Often called "people skills," they tend to incorporate both your
innate personality traits and how you've learned to handle certain social
situations. Effective interpersonal skills can help you during the job interview
process and can have a positive impact on your career advancement.
Effective systems to deal with various types of interpersonal conflict
Describe the classification system for lasers based on relative hazard potential
Ans✓✓✓-The classification System for lasers-
- Class 1 is considered safe use reasonably foreseeable used
- Class 1M is similar to Class 1, but the beam is not safe if viewed with the aid of
magnifying optical instruments
- Class 1C is the contact application to skin, such as in cosmetic skin treatments
- Class 2 (for lasers emitting in the visible range) - low power devices - eye
protection is normally afforded by the aversion response and the blink reflex of
the eye.
verified answers
Comment on its value as a measure to control contaminants (dilution ventilation)
Ans✓✓✓-This method is only suitable where there is a relatively low
concentration of high WEL contaminant which is given off slowly. It is not suitable
where operators are in close contact with the source of contamination
Define 'Workplace exposure limit'. Ans✓✓✓-defined as "maximum concentration
of an airborne substance, averaged over a reference period, to which employees
may be exposed by inhalation".
Define anxiety and depressions Ans✓✓✓-Anxiety - "feeling of unease, such as
worry or fear that can be mild or severe" (NHS)
Depression is when you have feelings of extreme sadness, despair or inadequacy
that last for a long time.
Define the term ' relative humidity' Ans✓✓✓-Relative humidity is an expression
of the ratio of water vapour in air relative to the maximum concentration of water
vapour that would be required to saturate air at the given temperature
Define the WBGT heat stress index Ans✓✓✓-WBGT is a heat stress index used to
make a prediction of the heat stress on a worker carrying out a particular rate of
work.
WBGT is calculated from:
WBGT = 0.7 WB + 0.3 GT indoors
,or
WBGT = 0.7 WB + 0.2 GT + 0.1 DB outdoors
where:-
- WB is the wet build temperature
- GT is the globe thermometer temperature
- DB is the dry bulb temperature
The index value (WBGT) must be used in conjunction with empirical
recommendations (set out in ISO 7243) to indicate a level that is safe for most
people who are physically fit and in good health.
Different values are quoted to distinguish persons acclimatised or unacclimatised
to heat.
If conditions of exposure fluctuate, a time-weighted average exposure can be
derived and used
Define what the Equality Act 2010 means by a disabled person Ans✓✓✓-a
person is disabled if they have "a physical or mental impairment which has a
substantial and long-term adverse effect on their ability to carry out normal dat-
to-day activities".
Describe a test that can be used to detect genetic mutation Ans✓✓✓-The most
well known test is the Ames test.
,This involves exposing the mutagen to a specific strain of bacteria that will not
normally grow in a histidine-deficient growth medium.
Mutagens will cause a mutation in the bacteria allowing them to grow in a
histidine-free medium
Describe an example of a retrospective cohort study Ans✓✓✓-Asbestos exposure
and lung disease
2 populations are identified which differ only by the fact that one group has been
historically exposed to asbestos and the other has not.
Evidence of exposure is collected from health records.
Medical surveillance is then carried out to gather data about the prevalence of
lung disease in these 2 groups.
This is reinforced with other health data.
Statistical analysis is then carried out to see if a link between lung disease and
historic asbestos exposure can be proven to exist.
Describe how oxygen enters the bloodstream Ans✓✓✓-Inhaled air passes
through the nose or mouth, down the trachea, bronchi and bronchioles, into
alveoli.
Here, the very thin lining of alveoli and blood vessels flows oxygen to diffuse into
the bloodstream where it then diffuses into red blood cells and is bound to
haemoglobin. Carbon dioxide is excreted by the same process
Describe how the ear converts sound waves into nerve stimulation to the auditory
centre of the brain. Ans✓✓✓-The ear transmits nerve impulses to the brain as a
, result of detecting and transmitting mechanical vibration through the outer ear,
the middle ear and the inner ear.
Describe measures that can be taken to reduce individual stress by improving
work relationships. Ans✓✓✓-Interpersonal skills training:-
Interpersonal skills involve the ability to communicate and build relationships
with others. Often called "people skills," they tend to incorporate both your
innate personality traits and how you've learned to handle certain social
situations. Effective interpersonal skills can help you during the job interview
process and can have a positive impact on your career advancement.
Effective systems to deal with various types of interpersonal conflict
Describe the classification system for lasers based on relative hazard potential
Ans✓✓✓-The classification System for lasers-
- Class 1 is considered safe use reasonably foreseeable used
- Class 1M is similar to Class 1, but the beam is not safe if viewed with the aid of
magnifying optical instruments
- Class 1C is the contact application to skin, such as in cosmetic skin treatments
- Class 2 (for lasers emitting in the visible range) - low power devices - eye
protection is normally afforded by the aversion response and the blink reflex of
the eye.